Human behavior is not characterized by unanimity but by differences in expressions and emotions (Alland, 2003). Proponents assume that human behavior is guided by emergent norms. Individuals who come together have divergent views, some act spontaneously with each other, others express what they feel and still others are restrained in their behavior. These people interact with each other guided by symbols, and an emergent norm comes about (Loy, 2001). In the process of responding to each other, a revised definition of the situation comes about and then individuals act in terms this definition.
So, in rallies, riots, mobs or demonstrations, there are some participants who are highly excited, expressing anger, hate, or fear, and there are some who are more contained in the expression of their emotions. Moreover, the norm may also define limits to their behavior. Reference: 1. Loy, James D. Understanding Behavior: What Primate Studies Tell Us about Human Behavior. Oxford University Press. Place of Publication: New York. Publication Year: 2001. 2. Alland, Alexander Jr. Evolution and Human Behavior. Publisher: Natural History Press. Place of Publication: Garden City, NY. Publication Year: 2003.